I'm based in UK and have a Valiani, it's fine but if I had my time over I'd get either of the other two you mention due to the support.
If you buy a Valiani it will be from a company called D&J Simons and the word "Computerised" or computer anything, is not a word you associate with them. They use independent engineers.
With both of the others the support is approximately 1.5 trillion times better and comes from the people you write the cheque out to. Regards actual machine performance and software, you get what you pay for; the Gunnar will be the most expensive.
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